Sir William Roberts defines gout “as a constitutional disorder characterised by paroxysmal attacks of inflammation of the joints, associated with the formation of chalk-like concretions in and about the joints.” Sir William Osler regards gout as “a nutritional disorder, one factor of which is an excessive formation of uric acid, characterised clinically by attacks of acute arthritis, by the gradual deposition of urate of soda in and about the joints, and by the occurrence of irregular constitutional symptoms.” For myself, I would proffer the following definition, which, of course, the reader must accept provisionally, viz., pending the perusal of subsequent chapters, dealing with the pathology and clinical features of gout, and the inferences drawn therefrom as to the nature of the disease. _Definition._—Gout is an hereditary disorder, the _intrinsic_ element of which is an inborn instability of nuclein metabolism which may remain latent, but under the influence of _extrinsic_ factors, _infections_, becomes manifest, as betokened by local inflammatory tissue reactions in joints or elsewhere the specific character of which is attested by the associated _uratic deposition_. CLASSIFICATION At the present time, under the most liberal interpretation, the word “gout” comprises the following conditions, viz., acute and chronic articular gout, and the so-called ab-articular forms. But it is clear that not only the latter or _irregular_ manifestations, but even the former or _regular_ varieties of the disorder seem destined to undergo considerable pruning. As to the classical podagra—_acute_ articular gout—no question can arise as to the propriety of its retention in this category. But as to the _chronic_ articular types we are on less certain ground, and to discussion of this vexed question we now proceed. Let us take, for example, Sir Dyce Duckworth’s classification of the _arthritic_ types of gout. He distinguishes the following forms:— (1) Acute articular gout. (2) Chronic articular gout the latter (2) further subdivided into— (_a_) the “tophaceous” variety. (_b_) the “deforming” variety. Of these twain the “tophaceous” form need not detain us, and why? Simply and solely this—the _uratic deposits_ stamp the seal of specificity on the disorder. In short, the presence of _tophi_ places the “gouty” origin of the arthritis beyond the pale of cavil. Now, if we accept, as we must, the fact that _uratic deposition is the solitary unequivocal clinical criterion of gout_, we are not, I contend, justified in classing any _chronic_ arthritis as “gouty,” the victim of which does not exhibit _tophi_ of articular or ab-articular site, either clinically demonstrable or deducible from skiagraphic revelations.